Metal box staying strip



Jul 18, 1933. w D TAN ER 1,918,992

METAL BOX STAYING S'IIRIP Filed Sept. 30, 1930 l w m iffalmzys Patented Jul 18, 1933 1,918,992

UNITED STATES PATENT orrics WILLIAM D. STANGER, OF SEASIDE PARK, NEW JERSEY, ASSIGNOR T0 NATIONAL METAL EDGE IBOX COMPANY, OF PHILADELPHIA, PENNSYLVANIA, A COPARTNEB- SHIP COMPOSED OF LOUIS WOLF, ALBERT WOLF, HOWARD WOLF, AND ELIAS WOLF METAL BOX STAYING STRIP Application filed September 80, 1980. Serial No. 485,899.

My invention is an improvement on the the length of the transverse line of severance ordinary metal stay for joining the meeting 1s greater than the distance between the coredges of a box of pasteboard or other similar ners at the outer ends of the V-blade, so that t i l, those corners engage the metal of the strip It is customary to feed to a box staying within lts opposite longitudinal edges and machine a continuous fiat strip of metal such edge portions are, therefore, not subwhich has formed along its edges spaced- J tGd to a clean shearing action. It is not apart holes around which the metal has been practicable to avoid this by changing the upset to form prongs. The machine cuts shape of the knife, since the V must be of the oil" a suitable length of strip to form a stay, shape required to form the proper angle. along a transverse line about midway be- One ob ect of the invention is to so modify tween two adjacent pairs of opposing holes, the construction of the old metal strip or bends the strip into a shape suitable for apstay that the two holes and accompanying plication to the box, and clinches the prongs sets of prongs ad acent the severed transverse in the walls of a box which the operator has edge will not be damaged or distorted in the placed into the machine. The cutting is cutting operation and will perform their inalways done by the only practical knife in tended holding function in the same way and general use to cut and crimp, which is a with the same certainty as the other sets of shearing blade having a V-shaped notch prongs. Another object of the invention is therein, which notch has sharpened sides and to so form the strip that it will be subjected, cooperates with a straight ledger blade to entirely along its line of severance, to a clean sever the strip. Because of the shape of or true shearing action, thereby not only the cutting blade the outer portions of the avoiding mutilation of the strip adjacent its strip are cut first and the cut proceeds inend corners, but also prolonging the life of wardly, the vertex of the notch accomplishthe shearing blade. ing the last part of the cutting at a point In order to fully explain my invention, it intermediate the longitudinal edges of the is necessary to illustrate, in addition to the strip. In the final shearing and bending improved stay, the part of the machine that operation the extremity of the severed strip performs the customary operations above deis bent at an angle to the plane of the strip scribed. and forced into the material of the box in Fig. 1 is a plan view of the flat strip before order that no raw edge shall be exposed, with it is bent into an angular stay. the object of eliminating the danger of Fig. 2 is an edge view of the strip on the scratching the hand of the user of the comline 22 of Fig. 1 together with an end view pleted box, and the prongs are forced into the of the die. box material. Fig. 3 is a fragmentary view of the end Heretofore an incidental effect of the cutof the strip after the cutting and securing ting, bending and clinching operation deoperation. scribed is to distort and damage, not merely Fig. 4 is an elevation, partly sectional, of usually, but practically invariably, one or the die carrying the cutting blade and the both, usually both, of the sets of prongs adledger blade and a side edge view of the metal jacent the severed and bentsin end. These strip, associated with the anvil between which prongs, therefore, cease to effectively perand the die and strip the adjacent walls of form their securing function. It is well recthe box are confined at the conclusion of the ognized that the only part of the length of operation. the strip that is insecurely held is that part- Fig. 5 is an end view of aportion of Fig. 4. adjacent the severed end. Obviously this is The metal strip a is inserted through an just the part of the length of the strip which orifice in the ledger blade f, which is vertiit is most important to hold securely. cally slidable in the die It and is normally Another ob ectlon arises from the fact that held in the position shown in Fig. 4 by means of a spring 9. The die h and anvil I: have complementary V-shaped faces. When the adjacent box walls a: and the strip a are pos1- tioned as shown in Fig. 5, the downward movement of the die h carries with it the shearing blade 13, which, by its cooperation with the edge f of the ledger blade, severs the strip on a transverse line. In the same downward movement of the die the strip is bent into a V-shape conforming to the opposing faces of the die and anvil, the prongs b are forced into the box material, and the extremity of the strip adjacent the transverse severed edge is bent down and forced into the box material, as shown at a in Fig. 3.

The strip a is provided, as shown in Fig. 1 with holes 0 adjacent its edges, the prongs I) being formed by upsetting the metal in the hole-punching operation. A strip of the prior art is shown in the Escobales Patent No. 1,703,522, issued February 26, 1929. In such strips the end holes and prongs adjacent the bent-in severed end are so distorted and damaged that their securing function is impaired or destroyed.

In my improved strip adjacent holes 0 along each longitudinal edge are spacedapart a distance approximating the diameter of a hole. As in the old strip, each longitudinal edge comprises a series of arcuate (approximately semi-circular) scallops (1 corresponding to, and approximately concentrio with, the respective holes, but the indentations between scallops, instead of extending inward to a line tangential, or nearly so, to the outer edges of the holes, as in the old strip, extend inward to a line y approximately passing through the centers of the holes By so modifying the old strip it is found that in the staying operation hereinbefore described, when the strip is cut transversely along a line about midway between two adjacent pairs of holes 0 (for example, the line 22 of Fig; 1) the two sets of prongs 6 adjacent to the severed edge are not damaged by the shearing and bending-in operations and perform the described securing function to the samede ee that it is performed by the other sets 0 prongs.

It is also of importance that the described modification of the old strip afiords a shorter transverse shearing line so that, in the described operation of the shear' blade, the corners in Fig. 2 at the outer en of the V- blade are outside the longitudinal edges of the strip, which is thus subjected, entirely across its severed end, to a true and clean shearing action, thereby prolonging the life of the shearin blade as welLas avoiding mutilation of t e strip adjacent its end corners.

The central series of holes e have the advantages set forth in the above mentioned Patent No. 1,703,522, but they are no part of the present invention and may be omitted.

The depth of the scallops should not be substantially less than that described, but the depth may be greater thanthat described without departing-from the invention. The approximate depth described, however, is preferred in order that the strength of the strip and the securing function of the prongs may not be impaired.

Having now fully described my invention, what I claim and desire to protect by Letters Patent is:

A metallic strip for staying boxes having near its longitudinal edges substantially straight rows of holes and prongs extending from the peripheries of the holes, the holes of one row being respectively opposite the holes of the other row, the edges being scalloped approximately concentric to the holes, the indentations formed by the scallops extending inward to a longitudinal line which is approximately not less distant than the centers of the holes from lines tangential to the crests of the scallops, whereby the strip may be transversely severed between adjacent pairs of opposing holes, bent along its longitudinal center line against adjacent box walls and the extremity of the severed strip bent into engagement with the box material without mutilating the end corners of the severed strip or impairing the securing function of the adjacent prongs, and prolonging the life of the shearing blade.

WILLIAM D. STANGER. 

